// 成绩
class Score {
    Student student
    Float score = 0.0// 分数
    Exam exam
     
    static constraints = {
        student()
        score(size: 0..200,blank: false)
        exam() 
    }

    static mapping = {
       table 'xedu_score'
    }

    String toString() {
        "${exam} ${student} : ${score}分"
    } 
}
